If you were wondering what nitrogen was used for you have come to the perfect place. One of the largest uses of nitrogen is for ammonia. Liquid nitrogen is used for cryotechniquewhich which contain a very low temparature and used for the preparation of various nitrogenous fertilizer and compounds like ammonia, nitric acid, etc. Nitrogen is used to make bombs and in other materials that have to do with bombs which i am not to sure of. so i hope this all will help you if you were curious.